Stadium (n.) A kind of telemeter for measuring the distance of an object of known dimensions, by observing the angle it subtends; especially (Surveying), a graduated rod used to measure the distance of the place where it stands from an instrument having a telescope, by observing the number of the graduations of the rod that are seen between certain parallel wires (stadia wires) in the field of view of the telescope; -- also called stadia, and stadia rod..

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